Mike, you mean first you shell out Mega$ to buy an Hitachi SAN server, then to start using it with all the SAN features like load balancing, path failover, PCI hotplug support, ... you have to shell out some more and buy their software. Don't tell me: it is licensed per CPU, per server?
I can only say: SDD and/or SDDPCM come free of charge for DS6k or DS8k customers (was also the case for ESS), and I believe RDAC driver is included in the DS4k package also...
HTH,
p5wizard